London, Nov 11 (AFP) Violence at pro-democracy protests in Hong Kong that saw a police officer shoot a masked demonstrator and a man set on fire is "deeply disturbing", the British government said Monday.

"Today's events are deeply disturbing. We are seriously concerned by the ongoing violence, and the escalation between protesters and police," said a Foreign Office spokesman.

Hong Kong, a former British colony which was handed back to China in 1997, has been gripped by a wave of protests over the last five months.

Prime Minister Boris Johnson's Downing Street office earlier urged for "calm and restraint on all sides", saying he supports "the right to peaceful protects.

"Political dialogue is the only way forward and we want to see the HK authorities agree a path to resolve this situation," he added.

Protesters, who had already begun a city-wide day of action aimed at paralysing the international financial hub, reacted to the morning shooting by rampaging through train stations, barricading streets and vandalising shops throughout the day.

Hong Kong authorities said that both the demonstrator who was hot and the man set on fire were in critical condition in hospital. (AFP)

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